Richard de Clare "Strongbow" 2nd Earl of Pembroke born 1130 led the Anglo-Norman invasion of Ireland 1169 in the reign of Henry II married 1171 to Aoife Mac Murrough Princess of Leinster descendant of Brian Boru in 1172 he and his wife's uncle Archbishop Laurence O'Toole started the re-building in stone of Christ Church Cathedral Dublin.

The Marriage of Princess Aoife of Leinster with the Norman Richard de Clare (Strongbow) by Daniel Maclise (1854).

During the last days of the late king Henry II he promised William Marshal the hand and estates of Isabel de Clare (1172–1220). King Richard I Coeur de Lion confirmed the offer and so in August 1189 at the age of 43 the Marshal married the 17-year-old daughter of Richard de Clare (Strongbow) whose mother in law Princess Aoife of Leinster had close family links with the O'Carroll of Ely Munster Eire.

The Vatican City: Popes have generally resided within the Vatican City since the return from Avignon France in 1377. Teige O'Carroll of Ely after attending the Court of King Richard II of England at Westminster Hall in 1391 then attended the Papal Court in 1392. In 1395 Teige O'Carroll defeated the forces of King Richard II which had invaded Ely under the command of the King's cousin Roger Mortimer Earl of March. The Kingdom of Ely and the O'Carrolls had withstood the most powerful army in the world and repelled them out of their territory thus retaining the integrity of the ancient principality of Elie in the centre of Ireland until 1690.